Track element for self-laying track-type vehicle

ABSTRACT

A track for a track laying vehicle in which the individual track elements are joined together by a series of separate wire rope connectors which fit into recesses in the track element and are held in place by a bolted cover plate. Each track element has a pair of cams at each of four corners. One of the cams of each pair being curved upwardly and the other being curved downwardly such that rotational movement of one track element relative to the adjacent track element results in at least one cam one of one track element rolling on the surface of a cam on the adjacent track element.

United States Patent TRACK ELEMENT FOR SELF-LAYING TRACK- TYPE VEHICLE 9Claims, 2 Drawing Figs.

0.5. CI 305/40, 305/57 Int. Cl 862d 55/18 Field of Search 305/40, 37,39, 56, 57

Primary E.raminerRichard J. Johnson Attorney-Fetherstonhaugh and Co.

ABSTRACT: A track for a track laying vehicle in which the individualtrack elements are joined together by a series of separate wire ropeconnectors which fit into recesses in the track element and are held inplace by a bolted cover plate. Each track element has a pair of cams ateach of four cornei-s. One of the cams of each pair being curvedupwardly and the other being curved downwardly such that rotationalmove, ment of one track element relative to the adjacent track elementresults in at least one cam one of one track element rolling on thesurface ofa cam on the adjacent track element.

PATENTEDUEB 'IIBYI 3.625.574

FIG. 2

INVI'JNTUR D. PLASTINO TENT AGENTS TRACK ELEMENT FOR SELF-LAYINGTRACK-TYPE VEHICLE The present invention relates to tracks and inparticular to a track element for use with a track laying vehicle.

A very large number of track laying vehicles are in use at the presenttime and there exists a large variety of tracks and track elements. Themost common track element which is used in heavy earth moving equipmentand also in military vehicles comprises a metal grouser, which contactsthe ground, and some means of joining the individual track elementstogether, the most common means being a hinge pin. This type ofarrangement of course results in a tremendous amount of wearparticularly when these vehicles are used on rough terrain. For militaryvehicles the noise that results in such vehicles is objectionable. Thenumber of spare parts that must be carried is high since complete trackelements in addition to the pins joining the track elements and allnecessary bolts must accompany the vehicles as well as a very involvedmechanism for tensioning the track so that a complete track element canbe removed. In some designs the bolts which hold the various partstogether protrude through the grouser and actually contact the ground.These bolts of course are subjected to wear and as a result after havingbeen used for a short period of time these bolts must be cut off with atorch in order to remove the tread or track from the vehicle.

One attempt to provide a solution to these problems is shown in CanadianPat. No. 802,779 which issued on Dec. 31, [968. This track elementcomprises a grouser which contacts the ground and a guideplate orcoverplate which is bolted to the top of the grouser. The track elementsare joined together by a separate component piece which consists of twolimb elements which are joined by a strip of rubber in which there isembedded a series of cables. These cables stretch from one limb elementto the next and are secured to the limb elements by swagging. Sincethese limb elements are secured one in one grouser and the other to thegrouser of the next track element, there is flexing when one trackelement moves relative to the other. This motion of one track elementwith relation to the other is taken up by a series of curved cams on thelimb elements. Thus movement of one track element with the other resultsin a rolling motion of one cam over the surface of the other. Inaddition since the cams are offset one from the other they prohibitlateral movement of one track element to the next.

This scheme of joining track elements has proven to have several seriousdisadvantages. The number of components is small but when a breakoccurs, say in one cable which is embedded in the rubber, additionalfailures follow and as a result the whole component comprising the limbelement and the cables must be removed completely and replaced. The limbelements, since they grasp and secure the cables by swagging must be ofa malleable material and are quite soft. However the cams that ride oneupon the other must be made of this same material and the resultant wearon the cams is high.

It is therefore an object of the present invention to provide a trackelement which has reduced wear, is simple to repair in the field and thenumber of spare parts which must be kept on hand is at a minimum.

Accordingly the present invention provides a track element for a tracklaying vehicle comprising a series of identical track elementsconsecutively joined together, each of said elements comprising agrouser and a cover plate removably secured thereto, the adjacentelements forming the track being joined together by a plurality ofconnectors, said connectors each comprising a length of wire rope havinga ferrule at each end, the ferrule at one end of the connector beingadapted to fit within a recess in the grouser of one track element andthe ferrule at the other end of the connector being adapted to fitwithin a recess in the grouser of the adjacent track element, saidferrules being retained in the recess in the grouser by said coverplate, said grouser having at each corner an upwardly curving cam and adownwardly curving cam, the cams of adjacent track elements meshing witheach other such that rotational movement of one track element relativeto the adjacent track element results in one cam of said first trackelement rolling on the surface of a cam of the adjacent track element.

The following is a description by way of example of a certain embodimentof the present invention, reference being had to the accompanyingdrawing in which:

FIG. 1 is an isometric view of two adjoining track elements of thepresent invention.

FIG. 2 is a detailed drawing of the cable and ferrules used to join thetrack elements together.

Referring to FIG. 1 the track element is comprised of a grouser If whichis the main element of the track and it is that part of the trackelement which contacts the ground. Looking at one end of the grouser itwill be seen that there is an outer upwardly curved cam 13 and anadjoining inner downwardly curving cam 12. At the other side of the sameend of the grouser there is an outer downwardly curving cam 14 and anadjoining upwardly curving cam 15. The other end of the grouser hasthese same cams.

The adjoining track element of course is identical to the first and itwill be seen that the outer upwardly curved cam 13 of one track elementmeshes with an outer downwardly curved cam 14 of the second trackelement. In a similar manner the inner downwardly curved cam 12 of thefirst track element meshes with the adjoining inner upwardly curved cam15 of the next track element. The same meshing takes place at the otherend of the two track elements, thus any rotational movement of one trackelement relative to the other results in a rolling motion of one camover the surface of another with very little sliding taking place. Inaddition, since the cams interlock one with the other, upwardly curvedcams 13 being outboard of upwardly curved cams l5 lateral movement ofone track element relative to the other is prevented. In the same mannerdownwardly curved earns 14 are outboard of downwardly curved cams 12 ofthe adjoining track element at both ends of the track and again lateraldisplacement of one track element relative to the other is prevented.Since these cams are an integral part of the grouser they are made fromthe same very hard metal as the grouser and any wear resulting from onecam sliding or bearing on another is kept to a minimum. The grouser ispreferably formed from steel containing over 40 percent manganese.

The method by which the adjoining track elements are secured together isquite ingenious. The grouser I] has in its surface a series of recesses21 and a number of grooves extending from the recesses to the edge ofthe grouser. A number of steel cables are used to link the trackelements together. These cables are detailed in FIG. 2 and comprise ashort length of cable 18 with a cylindrical ferrule 19 swaged onto thecable at each end. The ferrules 19 are adapted to fit into the recesses21 in the grouser 11 and the cables 18 are adapted to fit into thegrooves 20. The other end of the cable is inserted into a correspondinggroove in the adjoining track element and the ferrule 19 fits into therecess 21 in this same adjoining track element. There do not appear tobe serious limitations on the number of cables which can be used. Itwould seem that two is probably the minimum, and 10 is consideredadequate for most applications. Fourteen cables as shown on the drawingshave been used to advantage but more could be used if additionalstrength were required. In a preferred embodiment, the steel cables areformed from a plow wire rope having a nylon core.

The ferrules are retained in the recess 21 by means of a coverplate 23which is bolted to the top of the grouser by a series of bolts 27 whichfit into threaded holes 28 in the grouser. The coverplate is providedwith sprocket wells 24 which correspond to similar sprocket wells 22 inthe grouser. These sprockets wells permit the driving sprockets on thevehicle to drive the track. The sprockets protrude completely throughthe track element and through the grouser so that any foreign matterwhich may be picked up will be forced through and not retained in thetrack element.

The coverplate is also provided with a guide hole 25 through which theguide in the grouser protrudes. This guide, of course, is used to alignthe track element with the vehicle and prevent it from sliding off toone side of the drive wheels and the support wheels of the vehicle.

It is felt in some cases that stretching may take place in the cables 18after a short period of use and if it is desired to tighten up thecables and thus bring the track elements closer together the presentinvention envisages the use of nylon inserts 29 which can be insertedbetween the ferrule and the grouser body thus bringing the adjacenttrack elements closer to each other.

On big advantage of the track element of the present invention is thevery small number of parts required in its assembly. The track comprisesa grouser, a coverplate. six bolts and a number of joining cables withswaged ferrules. The spare part problem is tremendously reduced. It isexpected that very few broken grousers will result from normal wear. Thecoverplates are protected and are subjected to very little wear.Certainly the bolts joining the coverplate to the grouser should not bebroken under normal circumstances. Some wear will result in the cablesand ferrules joining adjacent track elements, however, these are verysmall, being only about 4 inch long and about V4 inch diameter and alarge number of these can easily be carried with no storage problem.

The replacement of broken parts is also greatly simplified with thepresent design. The most common breakage of course occurs with thecables and ferrules joining the adjacent track elements. These can bereplaced simply by removing the six bolts 27 lifting off the coverplate23 and lifting out the broken cables. Since the adjoining track elementsusually would still be joined together by unbroken cables thereplacement of the broken ones is a very simple matter.

lt is further envisaged that the track element of the present inventioncan be usefully employed as a conveyor belt for bulk handling of heavycoarse materials. In such use many of the same problems are encounteredas with a track for track laying vehicles. The conveyor belt assemblyhas much the same configuration as the track element illustrated in FIG.1 with the material being conveyed resting on the side of the grouserwhich would normally contact the ground.

The individual thickness and strength of the connectors and the numberof connectors can be varied to suit specific requirements. This ofcourse can be done whether the track element is used on a track layingvehicle or as an element ofa conveyor belt.

What I claim is:

l. A track for a track laying vehicle, comprising a plurality ofidentical track elements serially connected together, each of said trackelements including a generally rectangularly shaped grouser providedwith recesses substantially across the width thereof and a cover plateremovably secured to said grouser and covering the upper surface of saidgrousers and a plurality of sets of individual and identical connectorsconnecting together every two adjacent elements of the track.

each of said connectors comprising a wire rope and a pair of ferrulessecured to the ends of said rope, the ferrules of the several connectorsin the set being independently held in the recesses of adjacent grousersby the respective cover plates so that when the cover plates areremoved, any one of the connectors in the set may be individuallyremoved without disturbing the others.

2. The device as defined in claim 1 together with upwardly curved camsand downwardly curved cams provided at the comers of the grouser of eachtrack element, said cams being arranged so that relative rotationalmovement of adjacent track elements results in rolling of the upwardlycurved cams of each element on the downwardly curved cams of the otherelement, the device being further characterized in that said cams areformed integrally with the grousers as a discrete entity from saidconnectors.

3. The device as defined in claim 1 together with a guide extending fromthe top of the grouser of each track element and protrudin through ahole in the associated cover plate.

4. The evice as defined in claim 1 which is further characterized inthat the grouser of each track element is formed of steel containingover 40 percent manganese.

5. The device as defined in claim 1 which is further characterized inthat the wire rope of each of said connectors is a plow wire rope havinga nylon core.

6. A track element for a track laying vehicle wherein a plurality ofidentical track elements are serially connected together to form thetrack, said track element comprising a grouser provided with recessessubstantially across the width thereof and a coverplate removablysecured to said grouser and covering the upper surface of said grousersand said recesses, and a plurality of sets of individual and identicalconnectors adapted to connect the track elements to an adjacent trackelement, each of said connectors comprising a wire rope and a pair offerrules secured to the ends of said rope, the ferrules at one end ofthe several connectors in the set being adapted to be independently heldin the recesses of said grouser by said coverplate so that when thecoverplate is removed, any one of the connectors in the set may beindividually removed without disturbing the others.

7. The track element as defined in claim 6 together with upwardly curvedcams and downwardly curved cams provided at the corners of said grouser,said cams being arranged so that relative rotational movement ofadjacent track elements results in rolling of the upwardly curved camsof each element on the downwardly curved cams of the other element, thetrack element being further characterized in that said cams are formedintegrally with the grouser as a discrete entity from said connectors.

8. The track element as defined in claim 6 together with a guideextending upwardly from the top of said grouser and protruding through ahole in said cover plate.

9. The track element as defined in claim 6 which is furthercharacterized in that said grouser is formed from steel containing over40 percent manganese.

1. A track for a track laying vehicle, comprising a plurality ofidentical track elements serially connected together, each of said trackelements including a generally rectangularly shaped grouser providedwith recesses substantially across the width thereof and a cover plateremovably secured to said grouser and covering the upper surface of saidgrousers and said recesses, and a plurality of sets of individual andidentical connectors connecting together every two adjacent elements ofthe track, each of said connectors comprising a wire rope and a pair offerrules secured to the ends of said rope, the ferrules of the severalconnectors in the set being independently held in the recesses ofadjacent grousers by the respective cover plates so that when the coverplates are removed, any one of the connectors in the set may beindividually removed without disturbing the others.
 2. The device asdefined in claim 1 together with upwardly curved cams and downwardlycurved cams provided at the corners of the grouser of each trackelement, said cams being arranged so that relative rotational movementof adjacent track elements results in rolling of the upwardly curvedcams of each element on the downwardly curved cams of the other element,the device being further characterized in that said cams are formedintegrally with the grousers as a discrete entity from said connectors.3. The device as defined in claim 1 together with a guide extending fromthe top of the grouser of each track element and protruding through ahole in the associated cover plate.
 4. The device as defined in claim 1which is further characterized in that the grouser of each track elementis formed of steel containing over 40 percent manganese.
 5. The deviceas defined in claim 1 which is further characterized in that the wirerope of each of said connectors is a plow wire rope having a nylon core.6. A track element for a track laying vehicle wherein a plurality ofidentical track elements are serially connected together to form thetrack, said track element comprising a generally rectangularly shapedgrouser provided with recesses substantially across the width thereofand a cover plate removably secured to said grouser and covering theupper surface of said grousers and said recesses, and a plurality ofsets of individual and identical connectors adapted to connect the trackelement to an adjacent track element, each of said connectors comprisinga wire rope and a pair of ferrules secured to the ends of said rope, theferrules at one end of the several connectors in the set being adaptedto be independently held in the recesses of said grouser by said coverplate so that when the cover plate is removed, any one of the connectorsin the set may be individually removed without disturbing the others. 7.The track element as defined in claim 6 together with upwardly curvedcams and downwardly curved cams provided at the corners of said grouser,said cams being arranged so that relative rotational movement ofadjacent track elements results in rolling of the upwardly curved camsof each element on the downwardly curved cams of the other element, thetrack element being further characterized in that said cams are formedintegrally with the grouser as a discrete entity from said connectors.8. The track element as defined in claim 6 together with a guideextending upwardly from the top of said grouser and protruding through ahole in said cover plate.
 9. The track element as defined in claim 6which is further characterized in that said grouser is formed from steelcontaining over 40 percent manganese.